/* * vim:ts=4:sw=4:expandtab * * i3 - an improved dynamic tiling window manager * © 2009-2013 Michael Stapelberg and contributors (see also: LICENSE) * */ #include #include #include #include #include #include #if PANGO_SUPPORT #include #include #endif #include "libi3.h" extern xcb_connection_t *conn; extern xcb_screen_t *root_screen; static const i3Font *savedFont = NULL; #if PANGO_SUPPORT static xcb_visualtype_t *root_visual_type; static double pango_font_red; static double pango_font_green; static double pango_font_blue; /* Necessary to track whether the dpi changes and trigger a LOG() message, * which is more easily visible to users. */ static double logged_dpi = 0.0; static PangoLayout *create_layout_with_dpi(cairo_t *cr) { PangoLayout *layout; PangoContext *context; context = pango_cairo_create_context(cr); const double dpi = (double)root_screen->height_in_pixels * 25.4 / (double)root_screen->height_in_millimeters; if (logged_dpi != dpi) { logged_dpi = dpi; LOG("X11 root window dictates %f DPI\n", dpi); } else { DLOG("X11 root window dictates %f DPI\n", dpi); } pango_cairo_context_set_resolution(context, dpi); layout = pango_layout_new(context); g_object_unref(context); return layout; } /* * Loads a Pango font description into an i3Font structure. Returns true * on success, false otherwise. * */ static bool load_pango_font(i3Font *font, const char *desc) { /* Load the font description */ font->specific.pango_desc = pango_font_description_from_string(desc); if (!font->specific.pango_desc) { ELOG("Could not open font %s with Pango, fallback to X font.\n", desc); return false; } LOG("Using Pango font %s, size %d\n", pango_font_description_get_family(font->specific.pango_desc), pango_font_description_get_size(font->specific.pango_desc) / PANGO_SCALE); /* We cache root_visual_type here, since you must call * load_pango_font before any other pango function * that would need root_visual_type */ root_visual_type = get_visualtype(root_screen); /* Create a dummy Pango layout to compute the font height */ cairo_surface_t *surface = cairo_xcb_surface_create(conn, root_screen->root, root_visual_type, 1, 1); cairo_t *cr = cairo_create(surface); PangoLayout *layout = create_layout_with_dpi(cr); pango_layout_set_font_description(layout, font->specific.pango_desc); /* Get the font height */ gint height; pango_layout_get_pixel_size(layout, NULL, &height); font->height = height; /* Free resources */ g_object_unref(layout); cairo_destroy(cr); cairo_surface_destroy(surface); /* Set the font type and return successfully */ font->type = FONT_TYPE_PANGO; return true; } /* * Draws text using Pango rendering. * */ static void draw_text_pango(const char *text, size_t text_len, xcb_drawable_t drawable, int x, int y, int max_width) { /* Create the Pango layout */ /* root_visual_type is cached in load_pango_font */ cairo_surface_t *surface = cairo_xcb_surface_create(conn, drawable, root_visual_type, x + max_width, y + savedFont->height); cairo_t *cr = cairo_create(surface); PangoLayout *layout = create_layout_with_dpi(cr); gint height; pango_layout_set_font_description(layout, savedFont->specific.pango_desc); pango_layout_set_width(layout, max_width * PANGO_SCALE); pango_layout_set_wrap(layout, PANGO_WRAP_CHAR); pango_layout_set_ellipsize(layout, PANGO_ELLIPSIZE_END); pango_layout_set_text(layout, text, text_len); /* Do the drawing */ cairo_set_source_rgb(cr, pango_font_red, pango_font_green, pango_font_blue); pango_cairo_update_layout(cr, layout); pango_layout_get_pixel_size(layout, NULL, &height); cairo_move_to(cr, x, y - (height - savedFont->height)); pango_cairo_show_layout(cr, layout); /* Free resources */ g_object_unref(layout); cairo_destroy(cr); cairo_surface_destroy(surface); } /* * Calculate the text width using Pango rendering. * */ static int predict_text_width_pango(const char *text, size_t text_len) { /* Create a dummy Pango layout */ /* root_visual_type is cached in load_pango_font */ cairo_surface_t *surface = cairo_xcb_surface_create(conn, root_screen->root, root_visual_type, 1, 1); cairo_t *cr = cairo_create(surface); PangoLayout *layout = create_layout_with_dpi(cr); /* Get the font width */ gint width; pango_layout_set_font_description(layout, savedFont->specific.pango_desc); pango_layout_set_text(layout, text, text_len); pango_cairo_update_layout(cr, layout); pango_layout_get_pixel_size(layout, &width, NULL); /* Free resources */ g_object_unref(layout); cairo_destroy(cr); cairo_surface_destroy(surface); return width; } #endif /* * Loads a font for usage, also getting its metrics. If fallback is true, * the fonts 'fixed' or '-misc-*' will be loaded instead of exiting. * */ i3Font load_font(const char *pattern, const bool fallback) { i3Font font; font.type = FONT_TYPE_NONE; #if PANGO_SUPPORT /* Try to load a pango font if specified */ if (strlen(pattern) > strlen("pango:") && !strncmp(pattern, "pango:", strlen("pango:"))) { const char *font_pattern = pattern + strlen("pango:"); if (load_pango_font(&font, font_pattern)) { font.pattern = sstrdup(pattern); return font; } } else if (strlen(pattern) > strlen("xft:") && !strncmp(pattern, "xft:", strlen("xft:"))) { const char *font_pattern = pattern + strlen("xft:"); if (load_pango_font(&font, font_pattern)) { font.pattern = sstrdup(pattern); return font; } } #endif /* Send all our requests first */ font.specific.xcb.id = xcb_generate_id(conn); xcb_void_cookie_t font_cookie = xcb_open_font_checked(conn, font.specific.xcb.id, strlen(pattern), pattern); xcb_query_font_cookie_t info_cookie = xcb_query_font(conn, font.specific.xcb.id); /* Check for errors. If errors, fall back to default font. */ xcb_generic_error_t *error; error = xcb_request_check(conn, font_cookie); /* If we fail to open font, fall back to 'fixed' */ if (fallback && error != NULL) { ELOG("Could not open font %s (X error %d). Trying fallback to 'fixed'.\n", pattern, error->error_code); pattern = "fixed"; font_cookie = xcb_open_font_checked(conn, font.specific.xcb.id, strlen(pattern), pattern); info_cookie = xcb_query_font(conn, font.specific.xcb.id); /* Check if we managed to open 'fixed' */ error = xcb_request_check(conn, font_cookie); /* Fall back to '-misc-*' if opening 'fixed' fails. */ if (error != NULL) { ELOG("Could not open fallback font 'fixed', trying with '-misc-*'.\n"); pattern = "-misc-*"; font_cookie = xcb_open_font_checked(conn, font.specific.xcb.id, strlen(pattern), pattern); info_cookie = xcb_query_font(conn, font.specific.xcb.id); if ((error = xcb_request_check(conn, font_cookie)) != NULL) errx(EXIT_FAILURE, "Could open neither requested font nor fallbacks " "(fixed or -misc-*): X11 error %d", error->error_code); } } font.pattern = sstrdup(pattern); LOG("Using X font %s\n", pattern); /* Get information (height/name) for this font */ if (!(font.specific.xcb.info = xcb_query_font_reply(conn, info_cookie, NULL))) errx(EXIT_FAILURE, "Could not load font \"%s\"", pattern); /* Get the font table, if possible */ if (xcb_query_font_char_infos_length(font.specific.xcb.info) == 0) font.specific.xcb.table = NULL; else font.specific.xcb.table = xcb_query_font_char_infos(font.specific.xcb.info); /* Calculate the font height */ font.height = font.specific.xcb.info->font_ascent + font.specific.xcb.info->font_descent; /* Set the font type and return successfully */ font.type = FONT_TYPE_XCB; return font; } /* * Defines the font to be used for the forthcoming calls. * */ void set_font(i3Font *font) { savedFont = font; } /* * Frees the resources taken by the current font. * */ void free_font(void) { free(savedFont->pattern); switch (savedFont->type) { case FONT_TYPE_NONE: /* Nothing to do */ break; case FONT_TYPE_XCB: { /* Close the font and free the info */ xcb_close_font(conn, savedFont->specific.xcb.id); if (savedFont->specific.xcb.info) free(savedFont->specific.xcb.info); break; } #if PANGO_SUPPORT case FONT_TYPE_PANGO: /* Free the font description */ pango_font_description_free(savedFont->specific.pango_desc); break; #endif default: assert(false); break; } } /* * Defines the colors to be used for the forthcoming draw_text calls. * */ void set_font_colors(xcb_gcontext_t gc, uint32_t foreground, uint32_t background) { assert(savedFont != NULL); switch (savedFont->type) { case FONT_TYPE_NONE: /* Nothing to do */ break; case FONT_TYPE_XCB: { /* Change the font and colors in the GC */ uint32_t mask = XCB_GC_FOREGROUND | XCB_GC_BACKGROUND | XCB_GC_FONT; uint32_t values[] = {foreground, background, savedFont->specific.xcb.id}; xcb_change_gc(conn, gc, mask, values); break; } #if PANGO_SUPPORT case FONT_TYPE_PANGO: /* Save the foreground font */ pango_font_red = ((foreground >> 16) & 0xff) / 255.0; pango_font_green = ((foreground >> 8) & 0xff) / 255.0; pango_font_blue = (foreground & 0xff) / 255.0; break; #endif default: assert(false); break; } } static int predict_text_width_xcb(const xcb_char2b_t *text, size_t text_len); static void draw_text_xcb(const xcb_char2b_t *text, size_t text_len, xcb_drawable_t drawable, xcb_gcontext_t gc, int x, int y, int max_width) { /* X11 coordinates for fonts start at the baseline */ int pos_y = y + savedFont->specific.xcb.info->font_ascent; /* The X11 protocol limits text drawing to 255 chars, so we may need * multiple calls */ int offset = 0; for (;;) { /* Calculate the size of this chunk */ int chunk_size = (text_len > 255 ? 255 : text_len); const xcb_char2b_t *chunk = text + offset; /* Draw it */ xcb_image_text_16(conn, chunk_size, drawable, gc, x, pos_y, chunk); /* Advance the offset and length of the text to draw */ offset += chunk_size; text_len -= chunk_size; /* Check if we're done */ if (text_len == 0) break; /* Advance pos_x based on the predicted text width */ x += predict_text_width_xcb(chunk, chunk_size); } } /* * Draws text onto the specified X drawable (normally a pixmap) at the * specified coordinates (from the top left corner of the leftmost, uppermost * glyph) and using the provided gc. * * Text must be specified as an i3String. * */ void draw_text(i3String *text, xcb_drawable_t drawable, xcb_gcontext_t gc, int x, int y, int max_width) { assert(savedFont != NULL); switch (savedFont->type) { case FONT_TYPE_NONE: /* Nothing to do */ return; case FONT_TYPE_XCB: draw_text_xcb(i3string_as_ucs2(text), i3string_get_num_glyphs(text), drawable, gc, x, y, max_width); break; #if PANGO_SUPPORT case FONT_TYPE_PANGO: /* Render the text using Pango */ draw_text_pango(i3string_as_utf8(text), i3string_get_num_bytes(text), drawable, x, y, max_width); return; #endif default: assert(false); } } /* * ASCII version of draw_text to print static strings. * */ void draw_text_ascii(const char *text, xcb_drawable_t drawable, xcb_gcontext_t gc, int x, int y, int max_width) { assert(savedFont != NULL); switch (savedFont->type) { case FONT_TYPE_NONE: /* Nothing to do */ return; case FONT_TYPE_XCB: { size_t text_len = strlen(text); if (text_len > 255) { /* The text is too long to draw it directly to X */ i3String *str = i3string_from_utf8(text); draw_text(str, drawable, gc, x, y, max_width); i3string_free(str); } else { /* X11 coordinates for fonts start at the baseline */ int pos_y = y + savedFont->specific.xcb.info->font_ascent; xcb_image_text_8(conn, text_len, drawable, gc, x, pos_y, text); } break; } #if PANGO_SUPPORT case FONT_TYPE_PANGO: /* Render the text using Pango */ draw_text_pango(text, strlen(text), drawable, x, y, max_width); return; #endif default: assert(false); } } static int xcb_query_text_width(const xcb_char2b_t *text, size_t text_len) { /* Make the user know we’re using the slow path, but only once. */ static bool first_invocation = true; if (first_invocation) { fprintf(stderr, "Using slow code path for text extents\n"); first_invocation = false; } /* Query the text width */ xcb_generic_error_t *error; xcb_query_text_extents_cookie_t cookie = xcb_query_text_extents(conn, savedFont->specific.xcb.id, text_len, (xcb_char2b_t *)text); xcb_query_text_extents_reply_t *reply = xcb_query_text_extents_reply(conn, cookie, &error); if (reply == NULL) { /* We return a safe estimate because a rendering error is better than * a crash. Plus, the user will see the error in his log. */ fprintf(stderr, "Could not get text extents (X error code %d)\n", error->error_code); return savedFont->specific.xcb.info->max_bounds.character_width * text_len; } int width = reply->overall_width; free(reply); return width; } static int predict_text_width_xcb(const xcb_char2b_t *input, size_t text_len) { if (text_len == 0) return 0; int width; if (savedFont->specific.xcb.table == NULL) { /* If we don't have a font table, fall back to querying the server */ width = xcb_query_text_width(input, text_len); } else { /* Save some pointers for convenience */ xcb_query_font_reply_t *font_info = savedFont->specific.xcb.info; xcb_charinfo_t *font_table = savedFont->specific.xcb.table; /* Calculate the width using the font table */ width = 0; for (size_t i = 0; i < text_len; i++) { xcb_charinfo_t *info; int row = input[i].byte1; int col = input[i].byte2; if (row < font_info->min_byte1 || row > font_info->max_byte1 || col < font_info->min_char_or_byte2 || col > font_info->max_char_or_byte2) continue; /* Don't you ask me, how this one works… (Merovius) */ info = &font_table[((row - font_info->min_byte1) * (font_info->max_char_or_byte2 - font_info->min_char_or_byte2 + 1)) + (col - font_info->min_char_or_byte2)]; if (info->character_width != 0 || (info->right_side_bearing | info->left_side_bearing | info->ascent | info->descent) != 0) { width += info->character_width; } } } return width; } /* * Predict the text width in pixels for the given text. Text must be * specified as an i3String. * */ int predict_text_width(i3String *text) { assert(savedFont != NULL); switch (savedFont->type) { case FONT_TYPE_NONE: /* Nothing to do */ return 0; case FONT_TYPE_XCB: return predict_text_width_xcb(i3string_as_ucs2(text), i3string_get_num_glyphs(text)); #if PANGO_SUPPORT case FONT_TYPE_PANGO: /* Calculate extents using Pango */ return predict_text_width_pango(i3string_as_utf8(text), i3string_get_num_bytes(text)); #endif default: assert(false); return 0; } }